Design and implementation of large-screen LED display system for exhibitions

Abstract: LED display system is a typical and widely used application of semiconductor technology. This paper designs an LED display system suitable for exhibitions. The display system is divided into hardware system and software system. Under the control of input signals, it completes functions such as data storage and update, screen display, and animation processing. The designed large-screen LED display system only needs to be supplemented by simple peripheral circuits to meet the use of large-screen LEDs in exhibitions, which enhances the universality of LED large screens. Practical applications show that the design is stable and reliable, and has strong practicality.

LED display technology, also known as LED technology, has received widespread attention due to its advantages such as long life and high brightness. Currently, large-screen LED displays are widely used in exhibitions, stadiums, stations and other places, and are mainly used to display animations, texts and other contents. LED technology is a hot semiconductor technology with good development prospects. For this reason, this paper studies the large-screen LED display system used in exhibitions and introduces the design and implementation of the LED display system in detail.

1 LED display system

The large-screen LED display system used in exhibitions consists of two parts: the control system and the display system. The display system is composed of multiple LED display drivers. In order to ensure the display effect of the LED display system, these display drivers need to select the same circuit during the design of the display system to avoid the display effect of the display system being affected by different circuits.

In the process of designing the entire large-screen LED display system, the display system and control system play a key role. According to the display principle of the LED display system, the designed LED display system structure is shown in the figure below. The LED display system displays text, animation and other contents, so the information in its memory needs to be continuously updated to help the display system update relevant information.

The large-screen LED display system is a system that displays and controls synchronously. It transmits the received signals and information to the receiving end of the LED system through the network and displays them on the large screen.

The LED display system is composed of different display modules, for example, a display unit composed of 16 display modules, and in each display unit, the vertical and horizontal pixels are different. In addition, the display circuit also contains other components, which together constitute the LED display system.

The control system structure of the LED display system is shown in Figure 2. In the control structure of the LED display system, the single-chip microcomputer is the control core. Each single-chip microcomputer contains a Flash memory, which is easy to use. At the same time, the program can be encrypted and the intellectual property rights of the system design can be protected. It has powerful functions and effects.

2 Large-screen LED display system design

Analyzing from the development of LED display systems, the larger the size of the LED display, the more pixels are needed, and the larger the amount of data required. In the process of data display, if multiple display methods are needed to display information, the cost of the required data volume is also increasing. According to the previous processing method, data processing and information display will interrupt the data display, which is unbearable for the low-speed single-chip microcomputer. Therefore, when applied in large-screen LED display systems, the display screen will not be smooth, which is not only difficult to meet the needs, but also easy to be damaged. Therefore, the capacity of the display buffer needs to be increased. Before the information is displayed, the data to be processed will be fully processed under certain display requirements, and the processed information will be placed in the display buffer, which is convenient for display and also reduces the time occupied by data processing.

During the operation of the large-screen LED display system, the information needs to be scanned one by one according to the amount of information, and the size and pixels of the display screen also need to be scanned. The display screen scanning and refresh speed of the large-screen LED display system

The speed is slow, the time taken is too long, and the image flickers during the scanning and refreshing process. For this reason, it is necessary to design the large-screen LED display system in a unitized manner. For example, a large-screen display has 256 lines, which can be divided into 8 units for scanning. Each unit only needs to scan 32 lines, and each unit has good versatility, so the scanning speed can be accelerated. The speed of data transmission will also affect the scanning and refreshing speed of the LED display system, which is also one of the important influencing factors. In the design of the large-screen display system, this problem needs to be taken into account. In order to reduce the time spent on data transmission, the frequency of the clock in the display system can be appropriately increased in the circuit, but it should be noted that this increase cannot exceed the relevant threshold, otherwise it will cause instability in the LED display system.

In the process of designing a large-screen LED display system, the structure and workflow of the hardware system need to be paid attention to. In the process of designing the software system, many problems will also arise. In the process of designing a small-screen LED display system, in order to achieve multiple display modes, in the process of display program design, data processing and display will be used simultaneously, but for the design of a large-screen LED display system, this method is completely inapplicable. In the design of a large-screen LED display system, there is a lot of data to be processed, and it takes a long time to process, which causes problems such as uneven display images. Therefore, improvements need to be made in the design process.

In addition, in the process of designing a large-screen LED display system, in addition to the above issues that need to be considered, issues such as communication distance must also be considered to provide prerequisites for the design and implementation of a large-screen LED display system.

3 Design of large-screen LED display system for exhibitions

The design of large-screen LED display system needs to be carried out from two aspects: hardware design and software design:

1) Hardware Design

The hardware design of the large-screen LED display system and the specific structure of the display circuit are shown in Figure 3.

Since there are many digital tubes in the display system, the distribution of digital tubes needs to be designed. If the number of digital tubes is 30, a 5x6 arrangement can be performed. During the driver driving process, the digital tubes can be displayed in a static or dynamic manner, and the data to be displayed can be transmitted through the single-chip microcomputer and the digital tube.

2) Software Design

In order to better ensure the display effect of the large-screen display system, certain measures need to be taken to effectively process the display driver. A display buffer is established in the digital tube array in the hardware design. The data to be displayed is buffered in the display buffer. When the display driver interrupt occurs, the buffered characters and information in the display buffer can be output to complete the display.

3) Circuit design

The driver controller used in the LED display system has high adaptability and can be powered by various power supplies. The output voltage is within a controllable range. The circuit design needs to be relatively simple and low cost. The circuit design is shown in Figure 4.

As can be seen from the figure, the circuit consists of two parts: full-wave and filter capacitors to complete the current output of the entire circuit. Each component in the entire circuit has its own role. For example, inductor L1 provides current to the drive circuit during the operation of the LED display system, ensuring the balance of current in the entire circuit and promoting the operation of the LED. Actual tests have proved that the system operates normally and stably, and because the peripheral circuit design is simple, it is easy to use in outdoor occasions such as exhibitions that require high mobility.

4 Conclusion

With the development of science and technology, the functions of LED electronic screens will be more perfect, and the operation will be safer and more stable in the future. The design of large-screen LED display systems will be continuously updated, the display screens will become larger and larger, and the data that needs to be processed will become more and more. Therefore, in the process of designing LED display systems, it is necessary to design them according to the characteristics and requirements of the display screen to meet daily use needs and expand the functions and functions of the LED display system.